1. Field
The following description relates generally to wireless network communications, and more particularly to performing handover.
2. Background
Wireless communication systems are widely deployed to provide various types of communication content such as, for example, voice, data, and so on. Typical wireless communication systems may be multiple-access systems capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, . . . ). Examples of such multiple-access systems may include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and the like. Additionally, the systems can conform to specifications such as third generation partnership project (3GPP), 3GPP long term evolution (LTE), ultra mobile broadband (UMB), evolution data optimized (EV-DO), etc.
Generally, wireless multiple-access communication systems may simultaneously support communication for multiple mobile devices. Each mobile device may communicate with one or more base stations via transmissions on forward and reverse links. The forward link (or downlink) refers to the communication link from base stations to mobile devices, and the reverse link (or uplink) refers to the communication link from mobile devices to base stations. Further, communications between mobile devices and base stations may be established via single-input single-output (SISO) systems, multiple-input single-output (MISO) systems, multiple-input multiple-output (MIMO) systems, and so forth. In addition, mobile devices can communicate with other mobile devices (and/or base stations with other base stations) in peer-to-peer wireless network configurations.
To supplement conventional base stations, additional base stations can be deployed to provide more robust wireless coverage to mobile devices. For example, wireless relay stations and low power base stations (e.g., Home NodeBs or Home eNBs, collectively referred to as H(e)NB, femto access points, femtocells, picocells, microcells, etc.) can be deployed for incremental capacity growth, richer user experience, in-building or other specific geographic coverage, and/or the like. In some configurations, such low power base stations are connected to the Internet and the mobile operator's network via broadband connection (e.g., digital subscriber line (DSL) router, cable or other modem, etc.). Some H(e)NBs associate with a closed subscriber group (CSG) access for restricting access (or providing an improved level of access) to certain devices or related users that are members of the CSG.
In addition, H(e)NBs can operate using varying levels of restriction, such as using an open access mode to allow access to substantially any device, using a closed access mode to restrict access to devices that are members of the CSG, or using a hybrid access mode to allow at least some level of access or service to devices that are not members of the CSG while allowing an increased level of access or service to devices that are members of the CSG. Moreover, a plurality of H(e)NBs can be associated with a given CSG and can thus advertise parameters of the CSG (e.g., at an enterprise, retail center, etc.). In this regard, a device can travel throughout a coverage area and can be handed over to one or more H(e)NBs in the CSG.